A lot of families have awkward generation gaps. I know a family that had two daughters two years apart, and had a 3rd daughter 19 years after the middle daughter was born. Talk about a big age gap! You really can’t expect your adult children to have the same kind of bond with their decades-younger siblings as they would with a sibling born in the same decade as them, especially one they grew up with. A big part of the sibling bond is the fact that you are the only people who really know what your parents are like, and two sisters born 20 years apart grow up with very different parents, even if those parents are the same people in name. A 20-year-old mom and a 40-year-old mom are not going to parent their kids the same way, and that’s okay! Siblings can find other ways to bond even with a big age gap between them.